Using an expanded polytetrafluoroethylene conduit, a subclavian artery-to-pulmonary artery shunt was created in an infant with tetralogy of Fallot. The postoperative course was complicated by sepsis, shunt occlusion, and pneumonia. Four years later, an obstructive mass was found in the right main bronchus on fluoroscopy and was retrieved on rigid endoscopy, which turned out to be the migrated conduit. This case implies that a vascular conduit anastomosed to a systemic artery can migrate into the airway without bleeding, pseudoaneurysm formation, or host artery occlusion.